Old World warblers are a large group of birds formerly grouped together in the bird family Sylviidae. They are not closely related to the New World warblers. The family held over 400 species in over 70 genera, and were the source of much taxonomic confusion. Two families were split out initially, the cisticolas into Cisticolidae and the kinglets into Regulidae. In the past ten years they have been the subject of much research and many species are now placed into other families, including the Acrocephalidae, Cettiidae, Phylloscopidae, and Megaluridae. In addition some species have been moved into existing families or have not yet had their placement fully resolved. A smaller number of warblers, together with some babblers formerly placed in the family Timaliidae and the parrotbills, are retained in a much smaller family Sylviidae.
Bush-warblers are small insectivorous songbirds of the genera Cettia, Horornis, and Bradypterus. They were formerly placed in the "wastebin" Old World warbler family. None of the genera as traditionally delimited are believed to be monophyletic.
Cettia is a genus of small insectivorous songbirds ("warblers") which make up the core of the newly recognized family Cettiidae. They were formerly placed in the Sylviidae, which at that time was a wastebin taxon for the warbler-like Sylvioidea. The range of this genus extends from Europe to southeast Asia.
The western olivaceous warbler, also known as isabelline warbler, is a "warbler", formerly placed in the Old World warblers when these were a paraphyletic wastebin taxon. It is now considered a member of the acrocephaline warblers, Acrocephalidae, in the tree warbler genus Iduna. It was formerly regarded as part of a wider "olivaceous warbler" species, but as a result of modern taxonomic developments, this species is now usually considered distinct from the eastern olivaceous warbler, Iduna pallida.
The eastern olivaceous warbler is a small passerine bird with drab plumage tones, that is native to the Old World. For the most part it breeds in southeastern Europe, the Middle East and adjacent western Asia, and winters in the northern Afrotropics.
The Japanese bush warbler, known in Japanese as uguisu (鶯), is an Asian passerine bird more often heard than seen. Its distinctive breeding song can be heard throughout much of Japan from the start of spring.
The brown-flanked bush warbler, also known as the brownish-flanked bush warbler, is a species of bush-warbler of the family Cettiidae. It was formerly included in the "Old World warbler" assemblage. It is found in South Asia.
The aberrant bush warbler is a species in the bush warbler family, Cettiidae. It was formerly included in the "Old World warbler" assemblage.
The Bougainville bush warbler or odedi is a bird species initially placed in the "Old World warbler" assemblage, but nowadays moved with its congeners to the new cettiid warbler family.
The yellow-bellied warbler is a species of bush warbler. It was formerly included in the "Old World warbler" assemblage.
The Benguet bush warbler, also known as the Benguet grasshopper-warbler, is a songbird species. Formerly placed in the "Old World warbler" assemblage, it is now placed in the newly recognized family Locustellidae. L. seebohmi was formerly known as russet bush warbler, but that name is now restricted to L. mandelli, formerly included in L. seebohmi as a subspecies but now considered a separate species. It is found in the mountains of northern Luzon in the Philippines.
The Palau bush warbler is a species of Old World warbler in the family Cettiidae. It is found only in Palau.
The Manchurian bush warbler, also known as Korean bush warbler, is a bird in the family Cettiidae. The species was first described by Robert Swinhoe in 1860. It is found in northeastern China.
The Tanimbar bush warbler is a species of bird in the family Cettiidae. It is found in Yamdena. Its natural habitat is subtropical or tropical moist lowland forest. It is threatened by habitat loss.
The shade bush warbler or shade warbler is a species of bird in the family Cettiidae. It is found only in Solomon Islands, where it is endemic to the island of Makira . Its natural habitats are tropical moist lowland forests and tropical moist montane forests above 600m. It feeds on insects in the undergrowth and on the ground.
The Fiji bush warbler is a species of bird in the family Cettiidae. It is endemic to the islands of Fiji. There are four subspecies occurring on all the main islands of the group. The species has been afforded its own genus, Vitia, in the past, but similarities of egg colour, song and morphology place it firmly within the Horornis bush-warblers.
The Philippine bush warbler, also known as the Luzon bush warbler, is a species of bird in the family Cettiidae. It was formerly conspecific with the Japanese bush warbler. It is found only in the Philippines in the Cordillera Mountain Range of northern Luzon. It is found in tropical montane forest.
Hume's bush warbler is a species of bush warbler. It was formerly included in the "Old World warbler" assemblage.
Horornis is a genus of small insectivorous songbirds ("warblers") which make up the core of the newly recognized family Cettiidae. They were formerly placed in the Sylviidae, which at that time was a wastebin taxon for the warbler-like Sylvioidea. The range of this genus occurs from southeast Asia throughout the western Pacific. The most recently described species is the Bougainville bush warbler from Bougainville Island.
